Re: [PATCH v2 17/18] fpga: dfl: fme: add global error reporting support

On Mon, Apr 29, 2019 at 4:13 AM Wu Hao [off-list ref] wrote:

Hi Hao,

The changes look good.  There's one easy to fix thing that Greg has
pointed out recently on another patch (below).

This patch adds support for global error reporting for FPGA
Management Engine (FME), it introduces sysfs interfaces to
report different error detected by the hardware, and allow
user to clear errors or inject error for testing purpose.

Signed-off-by: Luwei Kang <redacted>
Signed-off-by: Ananda Ravuri <redacted>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Wu Hao <redacted>

Acked-by: Alan Tull <atull@kernel.org>

---
v2: fix issues found in sysfs doc.
    fix returned error code issues for writable sysfs interfaces.
    (use -EINVAL if input doesn't match error code)
    reorder the sysfs groups in code.

+static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+       struct device *err_dev = dev->parent;
+       void __iomem *base;
+
+       base = dfl_get_feature_ioaddr_by_id(err_dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+       return scnprintf(buf, PAGE_SIZE, "%u\n", dfl_feature_revision(base));

Greg is discouraging use of scnprintf for sysfs attributes where it's
not needed [1].

Please fix this up the attributes added in this patchset.  Besides
that, looks good, I added my Ack.

Alan

+}
+static DEVICE_ATTR_RO(revision);

[1] https://lkml.org/lkml/2019/4/25/1050